MODELING OF PARTICLE MOVEMENT AND THERMAL-BEHAVIOR DURING HIGH-VELOCITY OXY-FUEL SPRAYING

A theoretical model is presented to investigate the particle mechanica l and thermal behaviour in the process of high velocity oxy-fuel (HVOF ) spraying. The model accounts for the various phenomena which influen ce the momentum and heat transfer during particle movement and heating . The mathematical formulation takes into account the fluid velocity d ependence on the particle density, internal heat conduction in particl es and their composite structure, steep temperature gradients near the particle surface and fluid parameter variations. Comparison with expe rimental data shows that the present model enables accurate prediction s to be made and optimal conditions of HVOF spraying to be established .